How to do tests of significance for a difference between two means - AP Statistics

Step 1: We need to use a 2-sample z test because there are 2 samples, boys and girls. The population standard deviation, , is known, so we can assume a standard distribution for each sample.

Step 2: This is a one-sided z test because the questions asks if the mean height of boys is greater than the mean height of girls.

Step 3: significance level, or alpha, is . This means we need a p-value less than in order to reject the null hypothesis . A z-score greater than would ensure a p-value less than .

The critical value for a -test with alpha set to 0.10 is 1.645.

Step 1: We need to use a 2-sample z test because there are 2 samples, boys and girls. The population standard deviation, , is known, so we can assume a standard distribution for each sample.

Step 2: This is a one-sided z test because the questions asks if the mean height of boys is greater than the mean height of girls.

Step 3: significance level, or alpha, is . This means we need a p-value less than in order to reject the null hypothesis . A z-score greater than would ensure a p-value less than .

The critical value for a -test with alpha set to 0.10 is 1.645.

Step 1: We need to use a 2-sample z test because there are 2 samples, boys and girls. The population standard deviation, , is known, so we can assume a standard distribution for each sample.

Step 2: This is a one-sided z test because the questions asks if the mean height of boys is greater than the mean height of girls.

Step 3: significance level, or alpha, is . This means we need a p-value less than in order to reject the null hypothesis . A z-score greater than would ensure a p-value less than .

The critical value for a -test with alpha set to 0.10 is 1.645.

Step 1: We need to use a 2-sample z test because there are 2 samples, boys and girls. The population standard deviation, , is known, so we can assume a standard distribution for each sample.

Step 2: This is a one-sided z test because the questions asks if the mean height of boys is greater than the mean height of girls.

Step 3: significance level, or alpha, is . This means we need a p-value less than in order to reject the null hypothesis . A z-score greater than would ensure a p-value less than .